"It's been happening everywhere," she told CNN affiliate KPRC. "I've always kind of felt that eventually it would happen here, too."

The mass shooting is now a huge wakeup call that no school is invincible -- no matter what precautions it takes.

But in the wake of this tragedy, some officials are calling for new precautions:

Limit entrances to schools: "We need to get down to one or two entrances into our schools." Texas Lt. Gov. Dan Patrick told CNN. "You have the necessary exits for fire, of course, but we have to funnel our students into our schools so we can put eyes on them."

Take lessons from Israel: Patrick also said security needs to be tougher at schools. "The Israelis have three focus on security, and that is to deter, detect and deny," he said. "And we have too many people who can get onto our school campuses with guns who are not deterred."

Put biometrics on gun triggers: Houston Police Chief Art Acevedo said he wants biometrics on guns to make sure unauthorized people don't use them.

"It's about holding the gun manufacturers accountable and requiring them to have safety measures such as biometrics on triggers," the police chief said.

"If we can put a man on the moon, and we can put spacecraft on Mars, we are the American people. We're a pragmatic nation. There's a lot that can be done."

'Real consequences' for unauthorized use of a firearm: Gun rights advocates have noted that the calls for banning assault weapons wouldn't have prevented the massacre in Sante Fe.

And they're right -- police said the suspect, Dimitrios Pagourtzis, used a shotgun and revolver. But Gov. Greg Abbott said the guns actually belonged to the teen's father.

In Texas, the unauthorized use of a weapon is a misdemeanor. And Acevedo said he wants "real, absolute consequences when people that aren't supposed to have firearms have them."

Some have speculated whether adding metal detectors or banning trench coats would help.

"It's that whole argument about civil liberties vs. keeping us safe and making it a police state," former FBI supervisory special agent James Gagliano said.

"If we want to treat this like parochial schools and having students come to school with a tucked-in shirt so you can see a beltline -- that's fair, and that's part of this discussion. (But) I think there will be some resistance to that. We don't want to take away all our civil liberties, we don't want to turn this into a police state. But unfortunately, we've got to look at doing something different."